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Vitamin D Levels Linked To Uterine Fibroid Risk

A research study from the National Institutes of Health has found that women who had enough vitamin D cut their risk for uterine fibroids by nearly one third. Fibroids are tumors that develop in the uterus which are not cancerous, but often cause pain and bleeding in premenopausal women. Because of discomfort, they are the leading cause of hysterectomies in the United States.

The study examined 1,036 women who were between the ages of 35 and 49 and lived in the Washington D.C. area between the years of 1996 and 1999. Women were screened for fibroids by non-invasive ultrasound and blood tests were used to examine the form of vitamin D that is found circulating through the body, 25-hydroxy D. For the purposes of the study a blood concentration of 20 nanograms per milliliter of blood was considered 'sufficient,' but many experts conclude that higher levels are important for a healthy lifestyle.

Vitamin D is produced by the body when a person spends time in the sun; the ultraviolet light from sunlight interacts with chemicals in the skin and helps the body to produce more vitamin D. Other sources of vitamin D come from fortified milk and vitamins.

Study participants who had higher levels of 25-hydroxy D in their blood had less change of having evidence of fibroids from ultrasound examinations. Additionally by asking participants how long they spend in the sun every day on average, those that sit more than one hour per day had a smaller risk of having fibroids. Sun exposure for more than an hour daily reduced the risk of fibroids by 40 percent.

"It would be wonderful if something as simple and inexpensive as getting some natural sunshine on their skin each day could help women reduce their chance of getting fibroids," said Dr. Donna Baird, Ph.D., a researcher at the National Institute of Environmental Health Sciences (NIEHS) which is part of NIH. Dr. Baird is currently conducting a study in Detroit to confirm the findings from Washington D.C.

If something as simple as an hour of sunlight a day could reduce fibroids, and the pain and medical expenses associated with them, then it should be an easy prescription to fill.